An artificial sphincter is commercially available from American Medical Systems, Inc. (AMS), Gordon Valley, Minn., and is disclosed in U.S. Pat. No. 4,222,377 issued Sep. 16, 1980.
The present invention is an improvement upon the AMS system which includes an inflatable cuff encircling the urethra with the cuff being maintained in an inflated condition by a pump whereby the urethra is intended to be occluded to urine flow from the bladder. If a person desires to void the bladder, a valve is manually operated which allows fluid pressure in the cuff to be relieved and fluid flows through the valve into the pump. Deflation of the cuff is totally dependent upon pressure within the cuff forcing the fluid out of the cuff and back to the pump. This is a slow process and there is need for a more instantaneous way to prepare the cuff for voiding the bladder. The first embodiment of the present invention provides an answer to this problem.
A second problem experienced with the AMS system is that the cuff maintains continuous pressure on the urethra in order to prevent undesired urine flow from the bladder. It is difficult to achieve the optimum pressure level considering the advantages and disadvantages of too much or too little pressure. The amount of pressure that will assure that there is no leakage will cause damage to the urethra by cutting off blood flow and too little pressure will result in bladder leakage. The second embodiment of the present invention provides an answer to this problem.